Display panels include memory that stores, for each pixel, the color to be displayed. Pixel memory retention times are on the order of tens to hundreds of milliseconds. However, an image may remain on the screen for viewing over an extended viewing period on the order of tens or hundreds of seconds, if not minutes. Thus, the pixel memory is periodically refreshed at what is known as a refresh rate.
Modern display panels typically include frame buffers, which are integrated into the display panel and provide memory retention to allow for the panel to “self-refresh.” Self-refresh techniques provide a significant boost to energy efficiency of display devices.